The creation of evil is not evil the 'acquisition' of or desire for evil rather is evil. For creation and bringing into existence look to all the consequences whereas such desire looks to a particular result since it is a particular relation.
For example there are thousands of consequences of rain falling and all of them are good. If through mistaken some people receive harm from the rain they cannot say that the creation of rain is not mercy they cannot state that the creation of rain is evil. For it is due to their mistaken and inclination that it is evil for them. Also there are numerous benefits in the creation of fire and all of them are good. But if some people receive harm from fire through their misuse of it and their faulty choice they cannot say that the creation of fire is evil; because it was not only created to burn them. Rather they thrust their hands into the fire while cooking the food through wrong and made that servant inimical to themselves.
In Short: The lesser evil is acceptable for the greater good. If an evil which will lead to a greater good is abandoned so that a lesser evil should not be a greater evil will then have been perpetrated. For example to amputate a finger which is infected with gangrene and has to be amputated is good and right although it is apparently an evil. For if it is not amputated the hand will be amputated and that would be a greater evil.
Thus the creation and bringing into existence of evils harms tribulations. Satans and harmful things is not evil and bad for they are created for the many important results they yield. For example. Satans have not been set to pester the angels and the angels cannot progress; their degrees are fixed and deficient. However in the world of humanity the degrees of progress and decline are infinite. There is an extremely long distance through which to progress from the Nimrod's and Pharaoh's as far as the veracious saints and the prophets.
Thus through the creation of Satans and the mystery of man's accountability and the sending of prophets an arena of trial and examination and striving and competition has been opened so that coal-like base spirits may be differentiated and separated out from diamond-like elevated spirits. If there had been no striving and competition the potentialities in the mine of humanity which are like diamonds and coal would have remained equal. Since the creation of Satans and evils looks to great and universal results their being brought into existence is not evil or bad. The evils and instances of bad that arise from abuses and the particular causes known as inclination or choice pertain to man's 'acquisition' and choice not to Divine creation.
Question: The majority of humanity become unbelievers due to the existence of Satan and embrace unbelief and suffer harm despite the sending of prophets. If according to the rule "the majority has the word." the majority suffers evil as a result then the creation of evil is evil and it may even be said that the sending of prophets is not a mercy. Is that not so?
The Answer: Quantity has no importance in relation to quality. The true majority looks to quality. For example if there are a hundred seeds of the date palm and they are not put beneath the earth and watered and so do not undergo a chemical reaction and manifest a struggle for life they are only a hundred seeds worth virtually nothing. But if they are watered and are subject to the struggle for life and then eighty out of the hundred rot due to their faulty make-up but twenty become fruit-bearing trees can you say. "watering them was evil because most of them rotted?" Of course you cannot say that for that twenty have become like twenty thousand. One who loses eighty and gains twenty thousand suffers no harm and it cannot be evil.
And for example a peahen lays one hundred eggs and they are worth some dollars. If the hen sits on the hundred eggs and eighty are spoilt and twenty hatch into peacocks can it be said that there was a high loss and the affair was evil; that it was bad to put the broody hen on the eggs and an evil occurred? No it is not thus; it is rather a good. For the peacock species and egg family lost eighty eggs worth some dollars but gained twenty peacocks worth fortune.
Thus through the sending of prophets and the mystery of man's accountability and through striving and fighting with Satans in return for the hundreds of thousands of prophets and millions of saints and thousands of millions of purified scholars they have gained who are like the suns moons and stars of the world of humanity mankind has lost the unbelievers and dissemblers who are numerous in regard to quantity insignificant in regard to quality and like harmful beasts.